THIS INVENTION relates to material conveyor systems. More particularly, the invention relates to an idler roller for a belt conveyor such as, for example, a troughed belt conveyor; and to a belt conveyor system incorporating said idler roller. The invention further extends to a method for reducing breakaway mass of an idler roller.

BACKGROUND TO THE INVENTION Material conveyor systems and more particularly bulk material conveyor systems are typically used in mining operations to transport ore or coal from one point to another. Usually, conveyors of the troughed belt type are used for this purpose. Such conveyors are commonly made up of a supporting framework or base with integral brackets for supporting rollers, which may be driving rollers or idler rollers, upon which an endless belt is supported.

Conventional idler rollers of a fixed-form suspended idler system generally consist of a roll, having a roll shaft which is passed coaxial trough the centre of the roll, and an end cap fitted to each end of the roll. The roll shaft also passes through the centre of the end caps fitted at either end of the roll as it protrudes from both ends of the roll. The two end caps, one at each end of the roll, holds the rotating roll coaxial in position around the roll shaft, and the end caps are operable to rotate with the roll. Bearings, having an inner race and an outer race, are fitted into the end caps between the roll and the roll shaft such that the roll can rotate around the roll shaft which, importantly, remains stationary as the conveyor belt rolls over the roll. To achieve this, the operatively stationary roll shaft is passed through the inner race, and thus keeps the inner race stationary, while the outer race is brought into rolling contact with the end caps such that the outer race can turn with the roll. This arrangement allows the roll to rotate relative to the roll shaft.

Some of the perennial problems associated with these conventional idler rollers are that they are inclined to experience shaft deflection under load, causing misalignment between the inner and outer races of the bearings resulting in premature bearing failure. The roll diameter selected by industry combined with the practical geometry of the roll has limited the outer diameter of the bearing which will fit into the roll and thus the shaft diameter.

To illustrate the above, one can view the stationary roll shaft of a conventional idler roller as a structural support beam for the idler roller and the load on the idler roller between two support brackets on the base. Thus, when a conveyor belt is loaded, a downward force is transferred to the roll shaft at the bearings locations. These locations are not vertically in line with the two support brackets on the base and thus load distribution causes the shaft to deflect under load.

It is known that many idler roller manufacturers have attempted to increase bearing life by introducing shafts with increased diameters as well as larger bearings. Such dimensional changes contributed to an unwanted increase in roll mass. Rolls are also made with four bearings instead of two to improve the load carrying capacity of the rolls.

For example, when a roll is tested in accordance with one of the industry standards, it is stated that its breakaway mass shall not exceed 250g as that would require excessive power requirements to drive a conveyor belt over an array of said rolls. An idler roller with greater energy efficiency adapted to address the above problems is believed to hold great benefit.

Throughout the specification reference is made to terms which are common in the field of the art, and therefore the terms set out below are intended to mean the following:

Independently supported idler. A complete assembly comprising a base and roll.

Base: A manufactured steel frame that has integral brackets that support the roll. Roll: The revolving, cylindrical part of an idler, which is operatively in contact with a conveyor belt.

Roll shaft: The shaft about which the roll rotates. Breakaway mass: A mass that is applied tangentially to a periphery of a roll and which induces rotation of the roll.

Link supported idlers: Rolls connected to one another by means of connecting links on the ends of their roll shafts and suspended from a conveyor structure by means of a rigid or a flexible connection.

A link suspended conveyor belt idler system: A series of link supported idlers spaced apart and arranged to rotatably support a conveyor belt.

Fixed-form suspended idler system: A series of independently supported idlers spaced apart and arranged to rotatably support a conveyor belt.

SUMMARY OF THE INVENTION

In broad terms and in accordance with the invention there is provided an idler roller having opposing idler roller ends that can be fitted to a link suspended conveyor belt idler system or fixed-form suspended idler system, the idler roller comprising:

a rolling member operable to be positioned below, and in rolling contact with, a conveyor belt;

bearing means proximate each idler roller end for effecting relative motion between the rolling member and the idler roller ends, the bearing means including an inner race and an outer race; and

a restraining member connected, or connectable, to the outer race to restrain relative motion between the outer race and the rolling member, thereby allowing rolling contact between the inner race and the rolling member so as to effect rotation of the rolling member about the inner race.

There is also provided for the restraining member to be a brace which is integrally formed with the outer race and/or integrally formed with a central shaft that extends axially through the rolling member. Alternatively, the restraining member is a brace which is a unit separate from, and fastenable to, either the outer race or a central shaft that extends axially through the rolling member. There is further provided for the brace to comprise at least two attachment points, the first of which is fastened to the shaft while the second attachment point is fastened to an outer face of the outer race. Preferably, the respective attachment points are elongate legs which define either an u-shaped or inverted s-shaped brace in outline view.

In an embodiment of the invention two adjacent inner legs and to remote outer legs are provided, the inner legs being longer than the outer legs which hold the outer face stationary, the inner legs further defining a protrusion having a cavity for receiving the central shaft, which cavity is co-axial with an axis of rotation of the rolling member.

There is also provided for the restraining member to be a brace comprising interlocking means operable to engage the support bracket, which brace is integrally formed with the outer race. Alternatively, the restraining member is a brace comprising interlocking means operable to engage the support bracket, which brace is a unit separate from, and fastenable to, the outer race. It is envisaged that the interlocking means comprises a male or female formation operable to interlock a complementary shaped formation of the support bracket.

In an embodiment of the invention the brace comprises two opposing arms flanking an end portion of the brace and releasably fastened to the outer race, the arms defining a cylindrical hollow between them, which hollow is aligned with an axis of rotation of the rolling member having no central shaft.

It will be appreciated that the brace typically comprises a casting, moulding or a pressed sheet metal member.

There is also provided for the idler roller to include an interconnecting member to operatively connect, and ensure rolling contact between, the rolling member and an inner face of the inner race. Preferably, the interconnecting member is integrally formed with, or a unit separate from but attachable to, the rolling member.

In addition there is provided for at least one seal to be positionable or positioned in an aperture formed between the interconnecting member and the restraining member so as to prevent the ingress of dirt and moisture. The invention also provides for a troughed belt conveyor system that incorporates an idler roller as described herein above. Finally, the invention extends to a method for reducing breakaway mass of an idler roller, which method comprises:

providing an idler roller having opposing idler roller ends that can be fitted to a link suspended conveyor belt idler system or fixed-form suspended idler system, the idler roller comprising:

a rolling member operable to be positioned below, and in rolling contact with, the conveyor belt;

bearing means proximate each idler roller end for effecting relative motion between the rolling member and the idler roller ends, the bearing means containing an inner race and an outer race; and

connecting a restraining member to the outer race so as to restrain relative motion between the outer race and the rolling member, thereby facilitating rolling contact between the inner race and the rolling member and effecting rotation of the rolling member about the inner race. BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the invention are now described, by way of example, with reference to the accompanying non-limiting diagrammatic drawings. In the drawings:

Figure 1 shows a section view of a conventional idler roller, adapted to be fitted between two support brackets on a base supporting a conveyor belt;

Figure 2 shows a section view of the idler roller of Figure 1 , fitted between two support brackets on a base supporting a conveyor belt;

Figure 3A&3B shows longitudinal and transverse section views of an idler roller in an assembled configuration in accordance with a first embodiment of the invention;

Figure 4A&4B shows longitudinal and transverse section views of an idler roller in an assembled configuration in accordance with a second embodiment of the invention;

Figure 5A&5B shows longitudinal and transverse section views of an idler roller in an assembled configuration in accordance with a third embodiment of the invention ; Figure 6A&6B shows longitudinal and transverse section views of an idler roller in an assembled configuration in accordance with a fourth embodiment of the invention;

Figure 7 shows an exploded section view of an idler roller in accordance with a fifth embodiment of the invention;

Figure 8 shows a longitudinal section view of the idler roller of Figure 7, in an assembled configuration;

Figure 9 shows an exploded perspective view of the idler roller of Figure 7;

Figure 10 shows a perspective view of the idler roller of Figure 7, in an assembled configuration;

Figure 1 1 shows a longitudinal side view of the assembled idler roller of Figure 7, in an operative position on support brackets of a base;

Figure 12 shows a longitudinal section view of an idler roller in an assembled and partially disassembled configuration respectively, in accordance with a sixth embodiment of the invention;

Figure 1 3 shows an exploded perspective view of the idler roller of Figure 1 2;

Figure 14 shows a perspective view of the idler roller of Figure 12 in an assembled configuration;

Figures 15A-1 5C show perspective and section views respectively of a modified version of the idler roller of Figure 12; and

Figures 1 6A-1 6B show longitudinal and transverse section views of an idler roller that resembles the idler roller shown in Figures 4A and 4B, but having a slightly modified seal configuration.

DETAILED DESCRIPTION OF THE DRAWINGS

In the drawings, like numerals generally indicate like components, unless otherwise indicated.

Reference numeral 10 generally refers to an idler roller in accordance with a first embodiment of the invention, while reference numerals 100, 200, 300, 400, and 500 generally refer to idler rollers in accordance with further embodiments of the invention.

Referring to Figures 1 and 2, a conventional idler roller 1 0.1 normally used in a fixed- form suspended idler system is shown. Idler roller 1 0.1 can be fitted into two support brackets 1 2.1 , as shown in Figure 2, on a base 14.1 supporting a conveyor belt (not shown), which conveyor belt operatively passes over a series of spaced apart idler rollers 1 0.1 with or without carrying a load. Idler roller 10.1 generally consists of a roll 16.1 , having a roll shaft 18.1 which is passed coaxially trough the centre of the roll 16.1 , and an end cap 20.1 fitted to each end of the roll 1 6.1 . The roll shaft 18.1 also passes through the centre of the end caps 20.1 fitted at either end of the roll 16.1 as it protrudes from both ends of the roll 1 6.1 . The two end caps 20.1 , one at each end of the roll 1 6.1 , holds the rotating roll 1 6.1 coaxial in position around the roll shaft 1 8.1 , and the end caps 20.1 are connected to, and thus, operable to rotate with, the roll 16.1 . Bearings 22.1 , having an inner race 42.1 and an outer race 44.1 , are fitted into the end caps 20.1 between the roll 1 6.1 and the roll shaft 1 8.1 such that the roll 1 6.1 can rotate around the roll shaft 1 8.1 which, importantly, remains stationary as the conveyor belt rolls over the roll 1 6.1 . To achieve this, the operatively stationary roll shaft 1 8.1 is passed through the inner race 42.1 , and thus keeps the inner race 42.1 stationary; while the outer race 44.1 is brought into rolling contact with the end caps 20.1 such that it can roll with the roll 1 6.1 . This arrangement allows the roll 1 6.1 to rotate relative to the roll shaft 18.1 . In comparison, idler rollers 10, 1 00, 200, 300, 400, and 500 shown in Figures 3A to 16B of the drawings are believed to be improvements on idler roller 10.1 .

Turning now to describe idler rollers 10, 1 00, 200, 300, which are shown in Figures 3A and 3B to 6A to 6B. These idler rollers may also be fitted to two support brackets 12 on a base supporting a conveyor belt (not shown), and includes a rolling member 1 1 , 1 1 1 , 21 1 , 31 1 which is operatively positionable in rolling contact below the conveyor belt. Idler roller 10, 100, 200, 300 also includes two opposing idler roller ends between which four restraining members or braces 20, 120, 220, 320 are located. Braces 20, 120, 220, 320 are arranged in pairs, with one pair directly opposite the other near opposite idler roller ends. Each brace in a pair of braces is arranged spaced apart but in line with the other brace so as to be slightly above the other. Additionally, idler roller 1 0 includes bearing means 22, 122, 222, 322 proximate each idler roller end but located within rolling member 1 1 , 1 1 1 , 21 1 , 31 1 for effecting relative motion between said rolling member and the idler roller ends. Evident from Figures 3A and 3B to 6A and 6B is that the bearing means 22, 122, 222, 322 includes an inner race 42, 142, 242, 342 and an outer race 44, 144, 244, 344 having an inner face 24, 124, 224, 324 and an outer face 26, 126, 226, 326 respectively. It will be appreciated that the outer face 26, 126, 226, 326 is operatively in contact with, but stationary relative to, the brace 20, 120, 220, 320 while the inner face 24, 124, 224, 324 is operable to rotate with the rolling member 11, 111,211,311.

Relative motion between the outer race 44, 144, 244, 344 and the rolling member 11, 111, 211, 311 is, thus, constrained by brace 20, 120, 220, 320 which is connected, or connectable, to the outer face 26, 126, 226, 326 thereby facilitating rolling contact between the inner face 24, 124, 224, 324 and the rolling member 11 , 111 , 211 , 311 and effecting rotation of said rolling member about the inner race 42, 142, 242, 342. The rolling member 11 , 111 , 211 , 311 further consists of an elongate cylindrical drum or roll 16, 116, 216, 316 and an interconnecting member 19, 119, 219, 319 to operatively connect, and ensure rotatable contact between, the roll 16, 116, 216, 316 and the inner face 24, 124, 224, 324 of the bearing means 22, 122, 222, 322. A stationary roll shaft 18, 118, 218, 318 is adapted to coaxially pass through the centre of the roll 16, 116, 216, 316, between the respective braces 20, 120, 220, 320, and terminates at the respective idler roller ends. The rotating roll 16, 116, 216, 316 replaces the original function of roll shaft 18.1 as a structural support beam for the conventional idler roller 10.1. Preferably, the roll shaft 18, 118, 218, 318 only acts as an opposing force stabilizer which, in use, stabilizes rotating motion of the roll 16, 116, 216, 316. Thus, the minor forces which the roll shaft 18, 118, 218, 318 would have to withstand allow same to be solid or hollow and manufactured from a variety of lightweight materials such as metal alloys and plastics. There is further provided for each brace 20, 120, 220, 320 to comprise at least two attachment points in the form of legs 33, 133, 233, 333 and 35, 135, 235, 335, the first of which is fastened to the shaft 18, 118, 218, 318 while the second leg is fastened to the outer face 26, 126, 226, 326. As shown in Figures 3A to 5B, the legs 33, 133, 233 and 35, 135, 235 define an u-shaped brace when viewed in outline whereas legs 333 and 335 of Figures 6A and 6B define a generally inverted s-shaped brace having leg 333 fastened to shaft 31 8 and leg 335 fastened to outer face 326.

In Figures 4A and 4B, the interconnecting member 1 19 is shown to have a generally u- shape when viewed in outline. However, in Figures 3A and 3B the interconnecting member 19 is shown to have generally s-shape when viewed in outline whereas in Figures 5A to 6B the interconnecting member 219, 319 is shown to have generally inverted s-shape when viewed in outline. In each of these embodiments of the interconnecting member 19, 1 19, 219, 31 9 one limb thereof is secured, or securable, to an inner surface of roll 1 6, 1 1 6, 21 6, 31 6 whereas another limb is rotatably in contact with the free inner race 24, 124, 224, 324. It will be appreciated that the brace 20, 1 20, 220, 320 and the interconnecting member 1 9, 1 19, 219, 319 may be a casting, a moulding or even a pressed sheet metal unit. A variety of materials may be used for manufacturing such as, for example, metal, plastic, ceramic, rubber or composite materials.

In these embodiments, each bearing means 22, 1 22, 222, 322 is a bearing that has an inner face 24, 1 24, 224, 324 adapted to fit snugly over an inner surface 40, 140, 240, 340 of each interconnecting member 19, 1 1 9, 219, 319 so that an internal wall 36, 1 36, 236, 336 which extends into each leg 35,135, 235, 335 can be fitted snugly over the outer face 26, 126, 226, 326.

Seals 46, 146, 246, 346, each having a different shape and configuration as shown in Figures 3A to 6B, are fitted, or fittable, between the interconnecting member 19, 1 19, 21 9, 319 and the brace 20, 120, 220, 320 or roll shaft 18, 1 1 8, 218, 318 so as to protect each of the bearing means by preventing the ingress of dirt and moisture into the rolling member 1 1 , 1 1 1 , 21 1 , 31 1 . The seals may be of the labyrinth type, contact type, or a combination of both.

Seals are known to create the most resistance to rotation, thus, the smaller the diameter of a seal the lesser the resistance in terms of friction surface and lever arm. Seal failure is also the greatest cause of idler roller failures. Therefore, Figures 1 6A and 1 6B are included in which are shown an idler roller that resembles idler roller 100 of Figures 4A and 4B, but which is slightly modified with the only major difference being that the modified idler roller of Figures 1 6A and 1 6B includes a relatively small diameter seal 146. Modified Seal 146 operatively fits snugly in an elongate cavity formed between an inner surface of an inner leg 133 of the brace 120 and an outer surface of an inner limb of interconnecting member 1 1 9.

Idler roller 400, shown in Figures 7 to 1 1 , depicts a fifth embodiment of the invention and may also be fitted to conventional support brackets 1 2.1 on a base 14.1 supporting a conveyor belt (not shown). Idler roller 400 includes a rolling member 41 1 , which is positionable in rolling contact below the conveyor belt, and a brace 420, operable to support the rolling member 41 1 on each of the two respective support brackets 12.1 . Additionally, idler roller 400 includes a bearing means 422 having an outer face 426 and inner face 424. It will be appreciated that the outer face 426 is operatively in contact with, but stationary relative to, the brace 420, while the inner face 424 is operable to rotate with the rolling member 41 1 . Relative motion between the outer face 426 and the rolling member 41 1 is, thus, constrained by the brace 420 which is connected, or connectable, to the outer face 426, thereby facilitating rolling contact between the inner face 424 and the rolling member 41 1 and effecting rotation of the rolling member 41 1 about the inner race 442.

The rolling member 41 1 consists of an elongate roll 41 6, a roll shaft 41 8, and an interconnecting member 41 9 to operatively connect, and ensure rotatable contact between, the roll 41 6 and the inner face 424 of the bearing means 422. The roll shaft 41 8 is adapted to coaxially pass through the centre of the roll 41 6 and through the centre of the respective braces 420 which can be snap-fitted to either end of the roll 41 6 as the roll shaft 418 protrudes from both ends of the roll 41 6. The rotating roll 41 6 replaces the original function of roll shaft 1 8.1 as a structural support beam for the conventional idler roller 1 0.1 . Preferably, the roll shaft 418 only acts as an opposing force stabilizer which, in use, stabilizes rotating motion of the roll 41 6. Thus, the minor forces which the roll shaft 418 would have to withstand allow same to be solid or hollow.

Each of the respective braces 420 includes engagement means 428, best shown in Figures 9 and 10, to allow each brace 420 to engage roll support slots (not shown), provided in the support brackets 1 2.1 on the base 14.1 . As can be seen in the drawings, the engagement means 428 is typically in the form of locating flats, complementary shaped to a roll support slot and provided on one side of each of the respective braces 420.

There is further provided for each brace 420 to include an annular internal wall 436 that defines a cylindrical hollow 438 flanking a rotating axis A of roll 41 6. Each of the respective braces 420 additionally includes an innermost wall 437 that defines a cavity 439 for locating ends of the roll shaft 418.

In this embodiment, each bearing means 422 is a bearing that has an inner face 424 adapted to fit snugly against an inner annular surface 440 of each interconnecting member 419 so that the annular internal wall 436 of each respective brace can be fitted snugly over the outer face 426.

Seals 446 can also be snap-fitted between the interconnecting member 419 and the brace 420 so as to protect each of the bearing means by preventing the ingress of dirt and moisture into the rolling member 41 1 . The seals 446 may be of the labyrinth and/or contact type and preferably, but not necessarily, are integrally formed with each brace 420.

Retaining means in the form of shoulders or hooks for retaining in position the roll shaft 41 8 and each bearing means 422 respectively, are provided on internal surfaces of the brace 420 and on the inner annular surface 440.

As depicted in Figures 8 and 1 1 , each brace 420 supports the roller shaft 41 8 on the two respective support brackets 12.1 such that the outer face 426 of the bearing 422 is operatively in contact with, but stationary relative to, the brace 420. In such a case, the inner face 424 is operatively in contact with the inner annular surface 440 of the interconnecting member 41 9 and, thus, also with the roll 416. Preferably, the roll 41 6 and interconnecting member 419 are integrally formed by way of a moulding, pressing, or machining process. However, the parts 41 6, 419 can also be manufactured from assembled parts or moulded components. A variety of materials can be used such as, for example, metal, plastic, ceramic, rubber or composite materials. It will be appreciated that the material from which the parts 41 6, 419 are made is not essential to the efficiency of the design of the idler roller 400.

In the sixth embodiment of the invention, which is depicted in Figures 12 to 14, the rolling member 51 1 of idler roller 500 consists of an elongate cylindrical drum or roll 51 6 which is flanked by two substantially cylindrical protrusions 517 at either side thereof. Typically, the roll 51 6 and the two protrusions 517 are coaxial.

The brace 520 supports each protrusion 517 on the two respective support brackets 51 2 such that the outer face 526 of the bearing means 522 is operatively in contact with, but stationary relative to, the brace 520. In such a case, the inner face 524 is operatively in contact with the protrusion 517 and, thus, with the roll 51 6. Preferably, the roll 51 6 and protrusions 517 are integrally formed by way of a moulding, pressing, or machining process. However, the parts 516, 517 can also be manufactured from assembled parts or moulded components. A variety of materials can be used such as, for example, metal, plastic, ceramic, rubber or composite materials. It will be appreciated that the material from which the parts 51 6, 517 are made is not essential to the efficiency of the design of the idler roller 10. As is clear from Figures 1 2 to 14, the idler roller 500 does not have a roll shaft such as shaft 18.1 . The roll 51 6 is either a solid or hollow cylinder, and each brace 520 includes interlocking means 528, operable to engage either of the two support brackets 512 on the base 514 supporting the conveyor belt. The interlocking means as shown in Figures 12 to 14 includes a female formation which forms part of the interlocking means 528 and is formed in a bottom portion of brace 520. The female formation is shaped to interlock a complementary shaped male formation 534 on the bracket 512.

Each brace 520 further includes an inner wall 536 that defines a cylindrical hollow 538 coaxially positioned relative to the rotating axis of the roll 51 6.

As shown in the drawings, the bearing means 522 is a ball bearing. It will however be appreciated that other bearing means, capable of effecting the same inventive result, does not fall outside the ambit of the invention. However, as shown in Figures 1 2 to 14, each bearing 522 has an inner face 524 adapted to fit snugly over an outer annular surface 540 of the protrusion 517 so that the inner wall 536 of each respective brace 520 can be fitted snugly over the outer face 526.

Seals 546, which are best shown in Figures 12, are also positioned between each roll 51 6 and each brace 520 in order to prevent the ingress of dirt and moisture into the rolling member 51 1 .

As depicted in Figure 12, retaining means in the form of laterally extending shoulders are provided on an end of each protrusion 517, the shoulders, in use, fitting inside the respective braces 520. The shoulders are shaped and configured to retain the respective bearings 522 in position between each respective brace 520 and protrusion 51 7.

Figures 15A to 1 5C show how idler roller 500, with minor modifications thereto, can be used in a link suspended conveyor belt idler system.

Idler roller 500 is, thus, not required to fit into a support bracket. Instead, three or five idler rollers 500 have transverse holes 501 drilled through idler roller ends or through peripheral portions of braces 520. It will be appreciated that braces 520 may take various shapes and configurations whilst retaining the main function to constrain movement of the outer face 526. Two metal plates or strips 503, each with two spaced apart holes 505, 507 at either end are used, one on either side of the roll 51 6 to link or hold respective idler roller ends or braces 520 of at least two adjacent idler rollers together in a 'chain'.

This alternative embodiment of idler roller 500 is also a shaft-less idler roller with a brace 520 (commonly referred to as an end-cap), which incorporates the seal 546 around the bearing means 522. Two flat metal strips, each with inner 505 and outer holes 507 at either end, are attachable to the transverse holes 501 of idler roller brace 520 via the two inner holes 505 whereas the outer holes 507 in the metal strips 503 attach to a metal strip of an adjacent idler roller to form a chain of link suspended idlers.

While preferred embodiments of the invention are shown and described, it will be understood that it is not intended to limit the extent of the invention, but rather it is intended to cover all modifications and alternate methods, including: methods, for manufacturing the idler roller 1 0, 100, 200, 300, 400, 500 and components thereof, falling within the spirit and the scope of the invention. The applicant believes that the idler roller 1 0, 100, 200, 300, 400, 500 of the present invention, at least in part, addresses shortcomings in conventional idler rollers for troughed belt conveyors in that the idler roller 10, 100, 200, 300, 400, 500 provides a sturdy, well protected and affordable alternative to the known art. The roller 1 0, 100, 200, 300, 400, 500 proposed in this invention rotates the inner races of the bearings in the roll. Rotating the smaller inner race of a bearing requires less energy compared to rotating the larger outer race of said bearing. Configuring the idler to rotate the inner races of the two internal bearings as opposed to rotating the outer races of the bearings as is customary in conventional idler rollers, reduces the required breakaway mass of the idler roller and thus the energy required to rotate the idler roll. Therefore, the applicant believes that the lighter rotating mass and associated reduced breakaway mass of the idler roller 10, 100, 200, 300, 400, 500 as used and described in this invention, will use less energy in operation during the life of the idler roller and will thus allow for more efficient conveyor belt systems.

The idler roller 10, 1 00, 200, 300, 400, 500 described in this invention, can also utilise the increased carrying capacity and increased rotating speed of larger bearings while retaining the outer diameter of the shell and standard gauge lengths to suite the different conveyor belt widths adopted around the world.